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<?php //echo preg_replace('/(?:(?!dog).)++/', '<$0>', 'where my dog is now?'); echo preg_replace('/(?!ba).|(*SKIP)ba(*F)/', '<$0>', 'aabaabaaaaabbb');
Output for 5.3.4 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.6 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
<a><a>b<a><a>b<a><a><a><a><a><b><b><b>
Output for 4.4.9, 5.2.5 - 5.2.17, 5.3.0 - 5.3.3

Process exited with code 137.
Output for 4.3.11, 4.4.0 - 4.4.8, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.4
Warning: preg_replace(): Compilation failed: nothing to repeat at offset 9 in /in/ELMNb on line 3
Output for 4.3.0 - 4.3.10
Warning: Compilation failed: nothing to repeat at offset 9 in /in/ELMNb on line 3
preferences:
191.72 ms | 401 KiB | 312 Q